Accessibility Tagging Issues in PDF Export from InDesign - Tags Reverting or Disappearing

Your PDF has tags but they are not structured. (I didn't study the entire document.)

Are your InDesign style names very long? 

It sounds like you're doing post-PDF-export remediation in Acrobat? Not certain what kind of fixing you're doing post-export, but I wonder how much of it can be done upstream in InDesign. I don't think that reading order should be something you need to fix post-export in Acrobat; you should be able to fix that kind of thing in InDesign before export. 

Do you have your stories threaded in reading order?

Do you have objects anchored to those stories?

Did you order your stories in the Articles panel?

Do you have your objects arranged in the Layers menu according to the reverse order in which they should be read?  (That is, first read at the bottom of the stack)

Do you have a separate layer for objects to be artifacted - to be excluded from the reading order? 

Here's a good thread to start with, if these questions come as a surprise

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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